Into thin air

Communications News, April, 1998

Canyon Independent School District (CISD) in Amarillo, Texas, used to run its administrative functions on an IBM AS/400 system located on one campus. Administrative information was transferred between 12 campuses on slow-moving, leased 9.6 Kbps modem lines, which created bottlenecks in the network. Only one campus had Internet access.

CISD needed to reduce AS/400 response time, so the district sought a faster medium for transferring essential administrative data between campuses. With an eye toward the future, they also wanted scalable links that would provide campus-wide Internet and e-mail services for students, faculty, and administrators.

The district's technology committee began formulating a five-year technology plan in March of 1997. First, they evaluated connectivity issues. They wanted to establish an infrastructure that would link all campuses together, creating a flat metropolitan area network (MAN) that would later be connected to the Internet.

MicroAge, Inc., a systems integrator for the project, presented the district with several connectivity options. These included laying and leasing fiber, T1, or T3 lines, or purchasing short-haul microwave connections. The first three options proved to be too expensive for the expansive 787-square-mile district. However, the distances between campuses were perfect for 23 GHz microwave technology.

Financial analysis revealed that purchasing 11 Racon 23 GHz microwave radios would yield a return on investment in five years, without recurring leasing costs. Microwave links also provided more than six times the bandwidth of T1 lines. Operating at 10 Mbps, they provided extra capacity for the district's expansion plans.

The region's low humidity and flat terrain helped to make the microwave solution a clear choice for the district. The shortest inter-campus connection is 10 blocks and the longest is nine miles. Except for several campuses located on a canyon plateau, the flat terrain provides clear line of sight. To establish the tricky connections, 150-foot and 80-foot towers had to be erected on two campuses to reach the plateau.

Installation began last October. "It went smoothly," says Mark Taylor, educational consultant at MicroAge. "I was surprised how easily the systems lined up and turned on. It was very easy to get the wireless side of the new Ethernet network up."

Ken Burt, director of data processing at CISD, agreed. "There was nothing difficult at all. We had no problem attaching the servers onto the microwave links and getting them to talk to one another." To make this smooth transition happen, Burt preconfigured new remote communication controllers with the proper SNA and TCP/IP settings.

The only glitch, if it could be called that, happened the day after the new links were installed. The microwave links were so fast that students at one school were logging onto the first available server, which happened to be the administration's server on a different campus. Burt easily solved this problem by inserting preferred-server statements.

Today the microwave systems are serving a PC-based c1lent/server MAN, as well as providing connectivity for the district's IBM AS/400 mini-computer to all locations within the district. They work transparently within the Ethernet MAN and are connected to 3COM switches via standard, seamless RJ-45 ports. Switches are used instead of slower-reacting routers to simplify the network configuration and eliminate the use of subnetting.

Racon's Remote Monitoring Systems (RMS) monitor the microwave signals. The RMS units, located indoors in a standard 19-inch rack, allow Burt to monitor microwave performance and operation from anywhere in his network.

Canyon's new network currently has 1,200 computers, and 200 more are being added for the teaching staff. Administrators use the wireless intercampus connections to transfer e-mail, accounting, payroll, and human resources data. Plans-are to set up the network so teachers can input grades and attendance records from their own classroom computers.

The school district has already completed its first Internet training session for faculty. After an Internet firewall is installed, it plans to extend the scope of training by offering evening Internet classes for teachers, students, parents, and the community.